A flight investigation in natural icing conditions was conducted to determine the effect of inlet ice formations on the performance of axial-flow turbojet engines. The results are presented for icing conditions ranging from a liquid-water content of 0.1 to 0.9 gram per cubic meter and water-droplet size from 10 to 27 microns at ambient-air temperature from 13 to 26 degrees F. The data show time histories of jet thrust, air flow, tail-pipe temperature, compressor efficiency, and icing parameters for each icing encounter. The effect of inlet-guide-vane icing was isolated and shown to account for approximately one-half the total reduction in performance caused by inlet icing.

"An investigation has been conducted in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 0.057-scale model of the modified Chance Vought XF7U-1 airplane. The primary change in the design from that previously tested was a revision of the twin vertical tails. Tests were also made to determine the effect of installation of external wing tanks" (p. 1).

Tests of a 1/5 scale model of a proposed 153-foot high-speed submarine have been conducted in the Langley full-scale tunnel at the request of the Bureau of Ships, Department of the Navy. The test program included: (1) force tests to determine the drag, control effectiveness, and static stability characteristics for a number of model configurations, both in pitch and in yaw, (2) pressure measurements to determine the boundary-layer conditions and flow characteristics in the region of the propeller, and (3) an investigation of the effects of propeller operation on the model aerodynamic characteristics. In response to oral requests from the Bureau of Ships representatives t hat the basic data obtained in these tests be made available to them as rapidly as possible, this data report has been prepared to present some of the more pertinent results. All test results given in the present paper are for the propeller-removed condition and were obtained at a Reynolds number of approximately 22,300,000 based on model length.

"An investigation has been made of a partial-span model of the tail surface designed for use on the Hughes Falcon (MX-904) missile to determine the aerodynamic characteristics of the tail and elevator including elevator hinge moment. Data obtained at Mach numbers of 1.62 and 1.96 in the Langley 9- by 12-inch supersonic blowdown tunnel are presented for the condition where the tail was attached to a segment of the foreshortened body" (p. 1).

Memorandum presenting a pressure-distribution investigation of a wing of a complete supersonic aircraft configuration as conducted in the 4- by 4-foot supersonic tunnel at Mach number 1.59 based on the mean aerodynamic chord. The experimental life and drag coefficients were less than those predicted by linear theory. Results regarding section pressure characteristics, section characteristics, spanwise characteristics, and overall wing characteristics are provided.

From Summary: "An investigation is being conducted to determine the performance of the 12-stage axial-flow compressor of the XT-46 turbine-propeller engine. This compressor was designed to produce a pressure ratio of 9 at an adiabatic efficiency of 0.86. The design pressure ratios per stage were considerably greater than any employed in current aircraft gas-turbine engines using this type of compressor. The compressor performance was evaluated at two stations."

"An analysis was made at flight Mach number of 0.9 to estimate performance of nuclear-energy-powered turbojet engine and optimum engine operating conditions and to determine gross weight and load-carrying capacity of airplane powered by such an engine. The size of airplane required to carry disposable load of 20,000 pounds was found to vary from approximately 300,000 to 900,000 pounds depending on assumptions. For a reactor tube-wall mean temperature of 2500 degrees R, turbine-inlet temperature of 2000 degrees R, reactor-free-flow-area ratio of 0.33, reactor-shielding-material specific gravity of 6.0, shielding thickness of 3.0 feet, and altitude of 30,000 feet, the airplane gross weight required to carry a 20,000 payload is 545,000 pounds" (p. 1).

From Summary: "A review of the status of the knowledge on turbine-blade cooling and a description of pertinent NACA investigations are presented. The current limitations in performance of uncooled and cooled engines are briefly discussed. Finally, the knowledge available and investigations to increase the knowledge on heat transfer, cooling-flow, and performance characteristics of cooled turbines are discussed."

The stage performance of the X24C-2 axial-flow compressor, as determined from radial distributions of total pressure and temperature measured in each stator-blade row, was investigated at design speed at weight flows corresponding to those of the maximum weight-flow, peak-efficiency, and surge points. The stage performance is presented as the measured stage pressure ratios and the calculated velocity diagrams. The average stage total-pressure ratio at the surge operating condition in the first stage was approximately 1.10; in the second stage, approximately 1.13; and in all remaining stages, approximately constant at a value of 1.15. Regions of inefficient flow are discussed so as to point out the reasons for the poor flow conditions.

Report discussing tests using a model of the Navy XP2V-1 to study its performance when ditched. From Summary: "Various landing attitudes, speeds, and conditions of damage were simulated. The performance of the model was determined and recorded from visual observations, by recording time histories of the longitudinal decelerations, and by taking motion pictures of the ditchings."

"An investigation of a 1/24-scale dynamically similar model of the Boeing B-47 airplane was made to determine the ditching characteristics and proper ditching technique for the airplane. Various conditions of damage, landing attitude, flap setting, and speed were investigated. The behavior of the model was determined from visual observations, motion-picture records, and time-history deceleration records. The results of the investigation are presented in table form, photographs, and curves" (p. 1).

Report presenting the aerodynamic properties of a model of a jettisonable nose section with a circular cross section as determined at low speed from an investigation in the 20-foot free-spinning tunnel. The results indicated that the aerodynamic characteristics of the nose were greatly affected by proximity to the fuselage. Even for a stabilized nose, it may be necessary to eject the nose forward forcibly in order to prevent high accelerations along the backbone of the pilot.

Report discussing testing to determine the aerodynamic characteristics of two semispan delta-wing configurations. Information about the lift characteristics, drag characteristics, pitching-moment characteristics, and comparison with other results is provided.

"Free-flight tests have been made to determine the drag at zero lift of several configurations of a missile having triangular wings and tails. Base-pressure measurements were also obtained for some of the configurations. The results show that increasing the wing thickness ratio from 4 to 6 percent increased the wing drag by about 100 percent at M = 1.3 and by about 30 percent at M = 1.8" (p. 1).

"An investigation was conducted at Mach number 1.90 to determine pressure recovery and mass-flow characteristics of series of perforated convergent-divergent supersonic diffusers. Pressure recoveries as high as 96 percent were obtained, but at reduced mass flows through the diffuser. Theoretical considerations of effect of perforation distribution on shock stability in converging section of diffuser are presented and correlated with experimental data. A method of estimating relative importance of pressure recovery and mass flow on internal thrust coefficient basis is given and a comparison of various diffusers investigated is made" (p. 1).

Performance and boundary-layer data were taken in a 12 degree 10-inch inlet-diameter conical diffuser of 2:1 exit- to inlet-area ratio. These data were taken for two inlet-boundary-layer conditions. The first condition was that of a thinner inlet boundary later (boundary-layer displacement thickness, delta* approximately equal to 0.034) produced by an inlet section approximately 1 inlet diameter in length between the entrance bell and the diffuser. The second condition was a thicker inlet boundary layer (delta* approximately equal to 0.120) produced by an additional inlet section length of approximately 6 diameters. Longitudinal static-pressure distributions were measured fro wall static orifices. Transverse total- and static-pressure surveys were made at the inlet and exit stations. Boundary-layer velocity distributions were measured at seven stations between the inlet and exit. These data were obtained for a Reynolds number (based on inlet diameter) range of 1 x 10(exp 6) to 3.9 x 10(exp 6). The corresponding Mach number range was from M = 0.2 to choking. At the maximum-power-available condition supersonic flow was obtained as far as 4.5 inches downstream from the diffuser inlet with a maximum Mach number of M approximately equal to 1.5. The total-pressure loss through the diffuser in percentage of inlet dynamic …

Report discussing an investigation into the lateral-control characteristics and the pitching-moment characteristics of a scale model of the X-1 wing-fuselage configuration. Information about the estimated variation of rolling effectiveness and wing-fuselage pitching-moment coefficient is described in detail.

Report presenting an investigation of hot-pressed molbdenum disilicide bodies produced by industrial processes at a temperature of 2950 degrees and a pressure of 3000 pounds per square inch. Results regarding the short-time tensile strength, stress-rupture data, compression strength, air-corrosion resistance, hardness, coefficient of linear thermal expansion, thermal conductivity, and density are provided.

Free-flight performance of five 16-inch-diameter ram-jet units was determined over range of free-stream Mach numbers of 0.50 to 1.86 and gas total-temperature ratios between 1.0 and 6.1 Time histories of performance data are presented for each unit. Correlations illustrate effect of free-stream Mach number and gas total-temperature ratio on diffuser total-pressure recovery, net-thrust coefficient, and external drag coefficient. One unit had smooth steady burning throughout the entire flight and encountered a maximum free-stream Mach number of 1.86 with a net acceleration of approximately 4.2 g's.

From Introduction: "This paper presents the results of the investigation of the wing alone and of the wing-fuselage configurations employing a wing with an unswept quarter-chord line, aspect ratio 4, taper ratio 0.6, and an NACA 65A004 airfoil section parallel to the air stream. The experimental results of a wing of identical plan from having an NACA 65A006 airfoil section which was tested as part of the transonic program are presented in reference 1.

Report presenting a method of generating variable Mach number supersonic flow in a channel of fixed geometry by the removal of air through uniform porous walls. Calculated porosity distributions are presented for several minimum-length nozzles designed to operate at Mach numbers up to 2.0. Experimental and analytical data is presented.

Report presenting an investigation concerned with the measurement of the characteristics of longitudinal-control devices for a wing-fuselage combination with a wing with the leading edge swept back 63 degrees. Most of the investigation was devoted to testing a 30-percent-chord, 50-percent-semispan elevon, but some used upper-surface spoilers. Results regarding the characteristics of the wing with the elevon undeflected and control-surface effectiveness are provided.

Memorandum presenting an analysis of commercial airplane fire records collected during a 10-year period ending July 1, 1948. Gasoline was found to be the initial combustible ignited in flight most frequently and is considered to be the most hazardous of the combustibles carried. Electrical-ignition sources are the most frequent flight-fire ignition source by a small margin, but the exhaust system is the most hazardous ignition source because it is so close to the lubricating and gasoline systems.

From Introduction: "An investigation of the high-speed aerodynamic characteristics of a modified delta wing in combination with a fuselage was conducted in the Langley high-speed 7- by 10-foot tunnel. The model was tested on the sting support system through a Mach number range of 0.40 to 0.90 with both free and fixed transition. Because of the nature of the transition effect, the results seemed to be of the general interest and are presented in the present paper."